Any two positive and negative numbers of equal value would equal zero, for example -2 + 2 = 0 or -937 + 937 =0 and so on.
The factor pairs of 36 are (36,1)(18,2)(12,3)(9,4) None of them add up to 16.
None. 251 is a prime number.
None. You do not have enough numbers to make even one combination.
None - its a prime number and can only be times by itself and one.
None. Because: Two or more even numbers can never add up to produce an odd number.
There are none (as far as i know)
The factor pairs of 36 are (36,1)(18,2)(12,3)(9,4) None of them add up to 16.
There are none. Two odd numbers added together equal a even number.
None. 251 is a prime number.
None. You do not have enough numbers to make even one combination.
There is none.
None of the factor pairs of 180 differ by 7. If you were asking for factors of -180 that added up to -7, you could use 2 and -9 or 3 and -10 or 5 and -12 but as originally stated, there aren't two whole numbers that satisfy your request.
None - its a prime number and can only be times by itself and one.
None. Because: Two or more even numbers can never add up to produce an odd number.
53
52
That exactly none or two are positive AND that the rest are negative. See if you can work out why I added the last part.